Distillation of bituminous material



I Nov. 20, 1923.

M. GERCKE DISTILLATION OF BITUMINOUS MATERIAL Filed April 21. 1921 2Sheets-Sheet 1 Nov. 20, 1923.

M. GERCKE DISTILLATION OF BITUMINOUS MATERIAL 2 Sheets-Sheet 2 FiledApril 21. 1921 6 Ger.nan

Patented Nov. 20, 1923. a

PATENT ornca.

XIII-[11315] canon, 01' PABIRG, mum HIGH, G.

I DWI-ION OI nn'umous 'ILTE'BIAL aa uumuna April :1,

Toaawhoms'tmayconcem: Be it known that I, Msxnmaax Gnnoxe, a citizen ofthe State of Prussia, Germany, residing at Pasing, near Munich, Bavariahave invented certain new an use provements in the Distillation ofBituminous Material, of which the followin is a specification.

is invention relates to the distillation 10 of bituminous material andmore especiallyv bituminous coal, bituminous brown coal or bituminousschist or shale. Fuels that are rich in bitumen and ammonia aredistilled by the action of heat, in retorts, retort-generators andsimilar contrivances, in order to recover tar, oils and ammonia. Thelower the temperature andthe higher the pressure applied, the more fluidproducts obtained; and the higher the temperature and the lower thepressure used, the more gases given ofi' in the operation. Thedistillates obtained at the lowest temperatures and the highestpressures are of special value. In Mond gas generators, in order torecover the greatest possible amount of ammonia compounds and tar thatcome over at low heat, the temperature of gasification is kept at thelowest possible point by blowing in large quantities of steam atatmospheric pressure. In other systems the same end is attained by meansof generators, and when the gasification is effected in retortstheresult is got by drawing oil the products of gasification at thepoint Where they arise, in such manner that these products are kept fromcontact with hot parts of the gasifying plant.

According to another well known process steam is introduced intovertical retorts used for the distillation of brown coal, through adistributing pipe fitted on the wall of the retort which is heatedexternally. e steam enters into the path of the fuel which sinks downbefore it and becomes superheated to a greater and greater degreethrough heat taken up from the glowing walls of the retort, due to theincreasing temperature as the bottom is approached. In these well knownprocesses of dist g coal and shale in open slow combustion furnaces,heated by the external action of direct fire, it is impossible toregulate exactly the temperature and pressure of um. sum 80. team.

the steam admitted, and the s d at which the fuel asses through the pat.

e su ject of my invention is a process by which the most valuableby-products resultlng from the gasification of the fuel treate(bituminous coal, bituminous shale, or bituminous brown coal) areextracted in a continuous operation, by the action upon the fuel of acurrent of superheated steam of adjustable temperature and ressure, insuch a manner that the fuel andt eby-products separated from it are notexposed to any higher temperature than that of the superheated steamused.

lgs. 1 and 2 of the drawings are diagrammatic representations of twoforms of apparatus for carrying out the new process. Figs. 3 and 4 arecross-sections through the distilling chamber.

In Fig. 1 A indicates the distilling chamber, constructed as a tubularboiler. B are charging sections and C discharging sections. D are doublewalled tubes disposed within the chamber and provided on the upper sidewith a large number of perforations to admit superheated ,steam. Thetubes are centred against the chamber shell and suitably supported.Endless conveyor chains E are arranged to pass through the tubes D. Thelinks or members of the chain are formed as steam pistons F, F F F,etc., which are rendered fluid tight against the cylindrical walls ofthe charging and discharging sections B and C by labyrinth packings. Asthe piston members of the chain are all of the same diameter and arerigidly connected one with another they are all subjected to the samepressure irrespective of position. The tractive effort on the pistons istransmitted throu h the chain.

The fuel to be distilled is fi rst comminuted and prepared for use. Itis then fed into a hopper G from which it is delivered at H into thespaces between the pistons of the conveyor chain. Thence it is carriedinto the charging sections B, where it is preheated to the temperatureof the saturated steam used in distilling. The sections B are surroundedby a steam jacket I), the steam entering at c and leaving at d.Thereafter the fuel passes through the tubes D, in which superheatedsteam plays around it on all sides. The steam passes into the chamber'Athrough a chamber A through connection J and flows out again throughapipe. J after it has given 11 its superheat to thefuel and has separatedt e by-products contained in the latter-.-. The liquid by-products andthe water of condensationflow off from the tubes D, as the drawingshows, at the lower end of the chamber A into a, collecting vessel K inwhich'the gas-liquor is collected, whilst the vapors and gaseousportions flow ofi' with the steam.

The fuel from which the by-products have thus been separated leaves thedistilling the discharge connections C and is removed fromfthe conveyorby the upper chain wheel L and deposited into a bunker M,

The by-products which are separated in the well-known manner from thegas-liquor and the steam, are subjected to further subject treatment asrequired.

In the form of apparatus shown in Fig. 1 the steam used in distilling iskept in continuous circulation .throu'gh' the distilling chamber'A, thegas-liquor collector K,. and a steam superheater P, by means of a steamblower, the object being to increase the quantity of by-products in thedistilling steam and the gas-liquor.

N is the steam boiler for working the steam jet blower O, and P is thesteam superheater. ,Q, is the combustion space of the steam boiler and Ris a feed water heater, utilizing the waste heat from. the steam boiler.

The regulation of the steam temperature required for extracting anddistilling the fuel and theregulation of the pressure are effected bywell-known means common to steam boilers.

Another form of the process forming the hygroscopic water contained inthe fuel to be treated for the recovery ofprimary tar is evaporated inthe first place by the direct action of an oil bath, consisting of heavyhydrocarbons with a high boiling;

point, and in which the fuel, or rather the aemaining dry mass isafterwards distilled nZr already described, to obtain primary tar orcoal oil.

In this form of the process a circulating oil bath, having a highboiling point and consisting of heavyanthracene oil, or any fraction ofcoal oil or brown coal oil having a high boilin point, or any otherresidual oil of low va ue, -a'cts firstly merely as an external heatingagent of the fuel that is forced into it. It drives off the water andthe volatile constituents of the fuel that have v a boiling point belowits own temperature. In the operation the oil penetrates into the poresof the fuel as the latter'is gradually freed from water and saturatesthe dry mass. As the fuel rises up out of the oil bath a Of the vapoursdriven off,

ready for subsequent use. the oil bath lS,.Of,c,Qu1'Se, the portion withof my invention is one in which the' means of superheated steam in theman- K the tubular boiler N and the lower stituents of the fuel and ofthe oil absorbed "by it that gasifiesat a point below the highesttemperature .of the superheated steam used are thusdriven off, and theextracted fuel, also the non-volatile residue of the oil, particularlythe pitch, remain-as a sort of half-coke-and are discharged in thatstate at the conclusion of the process. the-oil usedfor the highestboili iig pointand consequently it is the first to bedepositedinthefrac: tional condensation of theextracted matters. It canbe returned into the oil bath, unless it is preferred always to use newwaste crude oil and to refine it for the recovery of the more valuablefractions, using the process herein described. The residue consisting ofpitch and impurities, can be used to saturate the fuel and to increasethe caloric value of the dry extracted mass.

As will be understood from the foregoing remarks, the saturation of thefuel with oil from the oil bath takes place first, and thereafter thedistillation with. superheated steam is effected resulting in'thatportion of the oil. used for saturation which is volatile at thetemperature adopted for the distillation bein driven off again. I 1

T e apparatus used in this modified form of the process is showndiagrammatically in Fig. 2 and, as will be seen, in-its essentials it isthe same as the apparatus shown in' plied with water, and a part Nsupplied with oil having a high boiling point. The steam superheater Pis arranged between these two. The collecting vessel K for theseparation of the impurities, etc., that are carried over, is connectedof the boiler and with the distilling chamber A by pipes in such mannerthat-an oil bath is formed in the lower portion of chamber.

A through which the conveyor chain E passes carrying with it the fuelthat is constantly fed forward between the pistons F P, F, etc. By meansofacentrifugal pump S fitted in the pi ing, the oil bath is kept incontinuous circ ation through the collector ortion of the distillingchamber A. be boiler N?- is heated by the waste gases from. thecombustion space of N and by the steam superheater-P 'The oil bath takesup heat from the hot gases and transfers it to the inch The fuel is thuspreheated to the temperature of the oil and with the part N the tubularboiler 7 through a conduit indicated at J any water that may be presentis evaporatedin the oil bath. The fuel thus freed from water is conveyedthrough the oil bath by the conveyor chain and is then distilled forprimary tar or coal tar by superheated steam from the boiler N andsuperheater P in the manner already described in connection with theapparatus shown in Fig. 1. The aqueous vapours separated from the oilbat-h, originating from the water contained in the fuel, mix with thesteam used for distilling and with the hydrocarbon vapours that aredistilled over and pass away to enter into fresh combinations. The steamused for the distillation as well as the gaseous and vaporlike productsof distillation are discharged -Any loss of oil from the oil bath as byleakage past the packings of the pistons F F, F etc. is made good bypumping in oil of a high boiling point. The oil that has taken upimpurities while being used is collected in a receiver as shown in thedrawing and after purification it can be utilized again.

A special advantage of this particular form of the process. is thatbrown coal of very little value is not-only distilled for tar but alsohas its caloric value considerably improved by partial saturation withheavy anthracene oils. so that its value in use increases and the fieldof its utility is enlarged. Further, the heavy tar oil that isunsuitable for driving Diesel or other oil engines can be used forfiring in conjunction with brown coal, thus avoiding the use of specialoil firing arrangements which would otherwise be necessary.

I claim:

1. A process for distilling bituminous material which consists inpositively and continuously moving the material along and during suchmovement SllbJBCtlIlg 1t 1n 2.

closed chamber, without the use of external heat, to the action ofsuperheated steam in circulation and controllable as to temperature andpressure.

2. The process as specified in claim 1 which comprises also the step ofpreheating the bituminous material prior to subjecting it to the actionof the superheated steam.

3. The process as specified in claim 1, which comprises the step ofpassing the material to be treated through a bath of hot circulating oilthereby preheating the material and at the same time saturating it withthe oil.

4. A distillation plant comp-rising a distillation chamber, a tubularpassage havin perforated Walls extending through said chamber, anendless piston chain conveyor adapted to pass through said tubularpassage in an axial direction, and means for generating superheatedsteam and feeding it through said chamber.

5. A distillation plant comprising a distillation chamber, a tubularpassage having perforated Walls extending through said chamber, anendless piston chain conveyor adapted to pass through said tubularpassage in an axial direction, means for generating superheated steamand feeding it through said chamber, and a vessel connected with saidchamber for collecting gas liquor.

6. A distillation plant comprising a distillation chamber,

a tubular passage having perforated Walls extending through saidchamber, an endles piston chain conveyor adapted to pass through saidtubular passage in an axial direction, means for generating superheatedsteam. and feeding it through said chamber, and means for heating oiland causing said hot oil to circulate also through said chamber. 7

7. A distillation plant comprising a distillation chamber, a tubularpassage havin perforated Walls extending through said chamber, anendless piston chain conveyor adapted to pass through said tubularpassage in an axial direction, means for generating superheated steamand feeding it through said chamber, and means for heating oil with theWaste gases of said steam generator and causing said hot oil tocirculate also through said chamber.

8. A distillation plant comprising a distillation chamber, a tubularpassage with perforated Walls extending through said chamber, an endlesspiston chain conveyor adapted to pass through said tubular passage, anoil bath surrounding the lower part of said tubular passage, and meansfor causing superheated steam to pass through the space above said oilbath.

In testimony whereof I afiix m signature.

I MAXIMILIAN GRCKE

